The present invention relates to a pressure vessel which comprises a rigid envelope composed of a body and a cover, which respectively have two axially aligned fluid orifices, the cover being peripherally encased in the body and fixed to the latter, the said body and the said cover defining an annular groove which communicates with the interior of the envelope via a narrow passage, a flexible separator dividing the interior of the envelope into two fluid compartments of variable volume, which are respectively associated with the two said orifices, and the said separator passing through the said narrow passage and having a flange engaged in the groove.
During operation, the flexible separator moves and is subjected to substantial tensile stresses which tend to pull the flange out of the groove. The flange must therefore be rigidly held in this groove, and this makes it necessary to take precautions on assembly. Moreover, the flange must at the same time ensure a seal between the two compartments defined in the rigid envelope by the flexible separator.
These various conditions which must be satisfied by the flange generally result in complication of the construction in order to achieve satisfactory operation.
It has been observed that the flange must fill the groove properly, that is to say it must be mounted in the latter without play, so as to withstand the tensile stresses developed on the separator during operation, and to ensure the sealing function between the two fluid compartments.
For this purpose, it has already been proposed to make the flange oversize on all sides, relative to the groove, or also in a radial direction, that is to say parallel to the direction of the tensile stresses exerted on the separator in the region of the flange, during operation.
It has been found that these arrangements result in anchoring conditions which generally make it necessary to assemble the rigid envelope using a particular fitting, for example with the aid of an additional component, such as an annular support for anchoring the flange, and this increases the cost of construction.
The present invention relates to a pressure reservoir which does not exhibit these disadvantages and which makes it possible, with a simple construction and with a reduced number of components, comprising only the body and the cover of the rigid envelope and the flexible separator, to achieve excellent conditions for anchoring of the separator and for the seal between the compartments defined in the envelope by the separator.